Add AdGuard DNS filter support

docs/configuration/rule-set/adguard.md

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+---
+icon: material/new-box
+---
+
+# AdGuard DNS Filter
+
+!!! question "Since sing-box 1.10.0"
+
+sing-box supports some rule-set formats from other projects which cannot be fully translated to sing-box,
+currently only AdGuard DNS Filter.
+
+These formats are not directly supported as source formats,
+instead you need to convert them to binary rule-set.
+
+## Convert
+
+Use `sing-box rule-set convert --type adguard [--output <file-name>.srs] <file-name>.txt` to convert to binary rule-set.
+
+## Performance
+
+AdGuard keeps all rules in memory and matches them sequentially,
+while sing-box chooses high performance and smaller memory usage.
+As a trade-off, you cannot know which rule item is matched.
+
+## Compatibility
+
+Almost all rules in [AdGuardSDNSFilter](https://github.com/AdguardTeam/AdGuardSDNSFilter)
+and rules in rule-sets listed in [adguard-filter-list](https://github.com/ppfeufer/adguard-filter-list)
+are supported.
+
+## Supported formats
+
+### AdGuard Filter
+
+#### Basic rule syntax
+
+| Syntax | Supported        |
+|--------|------------------|
+| `@@`   | :material-check: | 
+| `\|\|` | :material-check: | 
+| `\|`   | :material-check: |
+| `^`    | :material-check: |
+| `*`    | :material-check: |
+
+#### Host syntax
+
+| Syntax      | Example                  | Supported                |
+|-------------|--------------------------|--------------------------|
+| Scheme      | `https://`               | :material-alert: Ignored |
+| Domain Host | `example.org`            | :material-check:         |
+| IP Host     | `1.1.1.1`, `10.0.0.`     | :material-close:         |
+| Regexp      | `/regexp/`               | :material-check:         |
+| Port        | `example.org:80`         | :material-close:         |
+| Path        | `example.org/path/ad.js` | :material-close:         |
+
+#### Modifier syntax
+
+| Modifier              | Supported                |
+|-----------------------|--------------------------|
+| `$important`          | :material-check:         |
+| `$dnsrewrite=0.0.0.0` | :material-alert: Ignored |
+| Any other modifiers   | :material-close:         |
+
+### Hosts
+
+Only items with `0.0.0.0` IP addresses will be accepted.
+
+### Simple
+
+When all rule lines are valid domains, they are treated as simple line-by-line domain rules which,
+like hosts, only match the exact same domain.